Safety-catch for lifts.



A. JENKINS.

SAFETY CATCH r03 LIFTs.

APPLIQATION FILED MAR. 1.1907.

Patented Oct. 13, 1908.

WITNLEELEI. V l-NVl-LNTUR- ALEXANDER JENKINS, or GARLISLE, IOWA.

SAFETY-CATCH FOR LIFTS.

Specification 01' Letters Patent.

Patented Oct. 13, 1908.

Application f led March 1, 1907. Serial No. 360,086.

To all whom it may concern:

' Be it known that I, ALEXANDER JENKINS, a citizen of the United States, residing in Carlisle, county of Polk, and State of Iowa, have invented a new and useful Improvement in Safety-Catches for Lifts, of which the following is a specification.

The object of my invention is to provide a means of severing the cable and securely grasping and suspending a runaway lift.

A further object is to attain same in such a simple manner and so quickly that none of the mechanism will be damaged further than severing the cable and permitting it to run out of its supporting pulleys.

Another object is to construct such a means in a simple, strong, durable and inexpensive manner.

My invention consists of certain details of construction hereinafter set forth, pointed out in my claims and illustrated in the accompanying drawings in which Figure I shows a side elevation of a portion of the overhead beam of an elevator shaft and the top plate I employ; Fig. II shows a side elevation of a portion of the top beam of a lift and a side elevation of my device mounted thereon; Fig. III shows a side elevation of my device and a portion of the top beam in section; Fig. IV shows a plan view of the same, and; Fig. V shows a plan view of my top plate.

Referring to the accompanying drawings the reference numeral 10 is used to indicate the top beam of an elevator or lift and the numeral 11 the base portion of my device mounted thereon. In the base portion 11 I have provided orifices as indicated by the dotted lines in Fig. II some of said orifices being for the purpose of receiving bolts 12 designed to secure my device to the beam 10 and two of said orifices being adjacent to the upright U shaped framework I employ for the purpose of receiving the operating cable 13 which is designed to pass downwardly through one of said orifices, be counter sunk in the top beam 10 and pass upwardly through the other orifice and be secured to itself above the horizontal'portion of the U shaped upright framework thus obviously securing the said cable to the frame-work.

The numerals 14 and 15 indicate the up. wardly extending arms of the U shaped;

frame-work said arms being exactly similar in every respect and broadened laterally near their upper extremities. Near each lateral edge of the upwardly extending arms in their broadened portions is a transverse orifice said orifices being in the same plane and those in one arm being designed to serve'as companions for the respective orifices in the other arm for the purpose of receiving and forming loose bearings for cylindrical shafts 16 and 17 respectively, secured to balanced levers 18 and 19 respectively. The two said levers are similar in every respect except that on the inner surface and near the base of the lever 19 is mounted a lug 20 the lateral sides of which project to a point to form a knife, while mounted in a like place on the lever 18 is a lug 21 with a blunt surface for purposes hereinafter stated. Near the upper portion on the outer surface and above the cylindrical shafts 16 and 17 respectively on the said levers are shoulders 22 and 23 respectively designed for purposes hereinafter set forth. The forward surface of each of said levers is beveled near the top to provide an opening between the said levers through which the cable 13 is designed to project when my device is in position on the lift. At the extreme upper part of each of said levers I have provided a second orifice 24 and 25 respectively designed to receive a connecting wire26 which is designed to hold the said levers in position their lower extremities projecting outwardly from the cylindrical shafts 16 an 17 when my device is in position on the lift. Theshafts 16and 17 mounted as stated are designed as pivotal mountings for the levers 18 and 19 respectively.

The numeral 27 indicates a ring the inner diameter of which is by construction slightly greater than thedistance between the shoulders of the levers 18 and 19 when my device is in position. The, said levers are by construction wider at their bases than at their tops the distance from the outer surface near the base of one to the outer surface of the other near its base when the levers are down, as will be hereinafter explained, being greater than the inner diameter of the ring 27.

The numeral 28 indicates the top plate I employ, said plate being designed to be secured by bolts to the overhead beam 29 and the numeral 30 indicates a circular transverse opening centrally located in said plate said opening being slightly smaller in diameter t an the diameter of the ring 27.

The numeral 31 indicates an opening through the overhead beam 29 designed to be in line with and larger than the opening 30.

The top plate 28 is mounted on the central portion of the overhead beam 29 and the cable 13 is designed to pass through the openings 30 and 31.

In practical operation my device being secured to the lift cable passes from the lower portion of the U shaped frame-work upward through the U part and between the levers 1S and 19 and through the openings 30 and 31 and thence to its motive power. The levers 18 and 19 being joined at their upper extremities by means of the wire 26 are distended at their lower extremities from the pivotal shafts 16 and 17. The ring 27 is resting on the said levers immediately below the shoulders 22 and 23. The lift being be yond the control of the operator rapidly approaches the top of the shaft and the upper parts of the levers 18 and 19 are forced through the opening 30 and the ring 27 being larger than the said opening is stopped thereby and is forced downward on the said levers thus breaking the connecting wire 26. The ring being forced downward on the levers forces the lower arts of the levers together thus causing the inife 20 and the blunt edged lug 21 to be forced against the cable and as the said knife and lug are forming a support for each other the knife will force its way through the cable and against the blunt lug. The cable being thus severed and released runs out-of its bearings falling to the bottom of the shaft. As the ring 27 is smaller in its inner diameter than the distance from the outer surface of one lever to the outer surface of the other at their base it cannot be forced off of the same but wedges itself near their base thus effectually holding the upper extremities of the said levers apart from the pivotal shafts 16 and 17. As by construction the shoulders 22 and 23 are above the pivotal i shafts 16 and 17 and as the distance between said shoulders is less than the diameter of the opening 30 it is obvious that the said shoulders will be forced through the said opening 30 and the ring being forced downward on said levers will cause the shoulders to spread when released from the sides of the opening 30. As the said shoulders are also by construction of such size that when. spread apart r and thus support the weight of the cage or lift thereon.

The manner of securing the cable to my device may be changed without altering my device the principal features of which are the cutting of the cable and spreading of the jaws of the levers to catch the cage and support it from the overhead beam.

Having thus described my ii'lvention what I claim and desire to secure by Letters Patent of the United States is:

' A safety catch for lifts comprising a U shaped frame-work adapted to be secured to the top beam of the cage and a propelling cable secured thereto; a pair of balanced levers, one provided with a knife and the other with a lug securedv to said. frame work, each of said levers being provided with. a shoulder and an orifice; a ring mounted on said levers; a wire designed to secure said levers together at their upper extremities; a top plate mounted centrally on the overhead beam of the elevator shaft and an orifice located eentrall therein; and an overheadv beam provided with an orifice all arranged and combined substantially as shown and described.

ALEXANDER JEN lil X S.

Witnesses BLANCIIE Snnowiou, 7mm. G. Ron. 

